Historical clue formulations

• Pseudopod formers — 2006-07-23
• Early zoology topic — 2005-10-20
• Single-celled protozoa — 2000-08-29
• One-celled pond dwellers — 2000-03-21
• Creeping protozoans — 1998-10-09
• They have pseudopods — 1998-07-08
• One-cellers — 1997-12-04
• They undergo mitosis — 1996-12-29